From ssm-bounces@ietf.org Mon Nov 14 21:26:41 2005 Received: from localhost.cnri.reston.va.us ([127.0.0.1] helo=megatron.ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1EbqWv-0000lo-2s; Mon, 14 Nov 2005 21:26:41 -0500 Received: from odin.ietf.org ([132.151.1.176] helo=ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1EbqWt-0000lg-Cg for ssm@megatron.ietf.org; Mon, 14 Nov 2005 21:26:39 -0500 Received: from ietf-mx.ietf.org (ietf-mx [132.151.6.1]) by ietf.org (8.9.1a/8.9.1a) with ESMTP id VAA21700 for ; Mon, 14 Nov 2005 21:26:07 -0500 (EST) Received: from smtp2.dei.uc.pt ([193.137.203.231] helo=smtp.dei.uc.pt) by ietf-mx.ietf.org with esmtp (Exim 4.43) id 1Ebqo0-00018D-BG for ssm@ietf.org; Mon, 14 Nov 2005 21:44:22 -0500 Received: from laptop ([85.138.126.61]) (authenticated bits=0) by smtp.dei.uc.pt (8.13.4/8.13.4) with ESMTP id jAF2Rkbu025768 (version=TLSv1/SSLv3 cipher=RC4-MD5 bits=128 verify=NO) for ; Tue, 15 Nov 2005 02:27:47 GMT Message-Id: <200511150227.jAF2Rkbu025768@smtp.dei.uc.pt> From: "Tiago Sousa" To: Date: Tue, 15 Nov 2005 02:26:04 -0000 MIME-Version: 1.0 X-Mailer: Microsoft Office Outlook, Build 11.0.6353 Thread-Index: AcXpi+0msejobDocSsmFvUIOiv2E2w== X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2527 X-FCTUC-DEI-SIC-MailScanner-Information: Please contact helpdesk@dei.uc.pt for more information X-FCTUC-DEI-SIC-MailScanner: Found to be clean X-FCTUC-DEI-SIC-MailScanner-SpamCheck: not spam (whitelisted), SpamAssassin (score=-4.398, required 3, autolearn=not spam, ALL_TRUSTED -1.80, BAYES_00 -2.60, HTML_MESSAGE 0.00) X-FCTUC-DEI-SIC-MailScanner-From: tmas@dei.uc.pt X-Spam-Score: 0.2 (/) X-Scan-Signature: d890c9ddd0b0a61e8c597ad30c1c2176 Subject: [ssm] IPv6 Multicast Throughput problems in 802.11 X-BeenThere: ssm@ietf.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Source-Specific Multicast List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1840438086==" Sender: ssm-bounces@ietf.org Errors-To: ssm-bounces@ietf.org This is a multi-part message in MIME format. --===============1840438086== Content-Type: multipart/alternative; boundary="----=_NextPart_000_0007_01C5E98B.EE4C4930" This is a multi-part message in MIME format. ------=_NextPart_000_0007_01C5E98B.EE4C4930 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Hello to all I am testing the PIM-SSM daemon (both freebsd and linux) and mrd6 (another IPv6 multicast routing daemon) in a wireless link. The problem I encountered with both pim6sd daemon and mrd6 is that I'm sending multicast traffic at 4 Mbps and the throughput in the mobile node (which is very near from de access point) rounds 40 kbps. I am using the mad-flute tool to send the multicast SSM traffic and the tcpdump plus trpr to analyze the data. I have also used IxChariot and the results are the same. Anyone knows why the throughput decreases so much in the wireless link? (The multicast TTL is well defined, I have experimented with several pci/pcmcia cards and drivers and several access points configurations (different channels and rates (801.11b and 802.11g)). The results are remain always the same). I would appreciate any help/hint that helps me to explain these results. Thanks. Tiago Sousa ------=_NextPart_000_0007_01C5E98B.EE4C4930 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Hello to all

I am testing the PIM-SSM daemon (both freebsd and = linux) and mrd6 (another IPv6 multicast routing daemon) in a wireless link. =

The problem I encountered with both pim6sd daemon and = mrd6 is that I’m sending multicast traffic at 4 Mbps and the throughput = in the mobile node (which is very near from de access point) rounds 40 = kbps.

I am using the mad-flute tool to send the multicast = SSM traffic and the tcpdump plus trpr to analyze the data. I have also used IxChariot and the results are the same.

Anyone knows why the throughput decreases so much in = the wireless link? (The multicast TTL is well defined, I have = experimented with several pci/pcmcia cards and drivers and several access points = configurations (different channels and rates (801.11b and 802.11g)). The results are remain always = the same).

I would appreciate any help/hint that helps me to = explain these results.

Thanks.

Tiago Sousa

------=_NextPart_000_0007_01C5E98B.EE4C4930-- --===============1840438086== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ ssm mailing list ssm@ietf.org https://www1.ietf.org/mailman/listinfo/ssm --===============1840438086==-- From ssm-bounces@ietf.org Tue Nov 15 10:17:09 2005 Received: from localhost.cnri.reston.va.us ([127.0.0.1] helo=megatron.ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1Ec2YX-0003pl-2v; Tue, 15 Nov 2005 10:17:09 -0500 Received: from odin.ietf.org ([132.151.1.176] helo=ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1Ec2YW-0003pe-6C for ssm@megatron.ietf.org; Tue, 15 Nov 2005 10:17:08 -0500 Received: from ietf-mx.ietf.org (ietf-mx [132.151.6.1]) by ietf.org (8.9.1a/8.9.1a) with ESMTP id KAA29908 for ; Tue, 15 Nov 2005 10:16:35 -0500 (EST) Received: from sj-iport-1-in.cisco.com ([171.71.176.70] helo=sj-iport-1.cisco.com) by ietf-mx.ietf.org with esmtp (Exim 4.43) id 1Ec2pl-0007TX-5t for ssm@ietf.org; Tue, 15 Nov 2005 10:34:58 -0500 Received: from sj-core-1.cisco.com ([171.71.177.237]) by sj-iport-1.cisco.com with ESMTP; 15 Nov 2005 07:16:58 -0800 X-IronPort-AV: i="3.97,333,1125903600"; d="scan'208"; a="675075980:sNHT1244517302" Received: from cisco.com (cypher.cisco.com [171.69.11.142]) by sj-core-1.cisco.com (8.12.10/8.12.6) with ESMTP id jAFFGtQe013454; Tue, 15 Nov 2005 07:16:56 -0800 (PST) Received: (from eckert@localhost) by cisco.com (8.8.8-Cisco List Logging/8.8.8) id HAA00228; Tue, 15 Nov 2005 07:16:55 -0800 (PST) Date: Tue, 15 Nov 2005 07:16:55 -0800 From: Toerless Eckert To: Tiago Sousa Subject: Re: [ssm] IPv6 Multicast Throughput problems in 802.11 Message-ID: <20051115151655.GL19539@cisco.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4i X-Spam-Score: 0.0 (/) X-Scan-Signature: 21c69d3cfc2dd19218717dbe1d974352 Cc: ssm@ietf.org X-BeenThere: ssm@ietf.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Source-Specific Multicast List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: ssm-bounces@ietf.org Errors-To: ssm-bounces@ietf.org What packet size do you use ? There's also a configuratin on access-points for how much bandwidth multicast (aka: broadcast) can use. That's often tuned down to a very low default value. I've used successfully multiple megabits across 802.11b, not sure what your problem is... On Tue, Nov 15, 2005 at 02:26:04AM -0000, Tiago Sousa wrote: > Hello to all > > > > I am testing the PIM-SSM daemon (both freebsd and linux) and mrd6 (another > IPv6 multicast routing daemon) in a wireless link. > > The problem I encountered with both pim6sd daemon and mrd6 is that I'm > sending multicast traffic at 4 Mbps and the throughput in the mobile node > (which is very near from de access point) rounds 40 kbps. > > I am using the mad-flute tool to send the multicast SSM traffic and the > tcpdump plus trpr to analyze the data. I have also used IxChariot and the > results are the same. > > > > Anyone knows why the throughput decreases so much in the wireless link? > (The multicast TTL is well defined, I have experimented with several > pci/pcmcia cards and drivers and several access points configurations > (different channels and rates (801.11b and 802.11g)). The results are remain > always the same). > > > > I would appreciate any help/hint that helps me to explain these results. > > > > Thanks. > > > > Tiago Sousa _______________________________________________ ssm mailing list ssm@ietf.org https://www1.ietf.org/mailman/listinfo/ssm From ssm-bounces@ietf.org Tue Nov 15 10:35:20 2005 Received: from localhost.cnri.reston.va.us ([127.0.0.1] helo=megatron.ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1Ec2q8-0008Nm-IH; Tue, 15 Nov 2005 10:35:20 -0500 Received: from odin.ietf.org ([132.151.1.176] helo=ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1Ec2q6-0008NZ-9w for ssm@megatron.ietf.org; Tue, 15 Nov 2005 10:35:18 -0500 Received: from ietf-mx.ietf.org (ietf-mx [132.151.6.1]) by ietf.org (8.9.1a/8.9.1a) with ESMTP id KAA00855 for ; Tue, 15 Nov 2005 10:34:45 -0500 (EST) Received: from smtp2.dei.uc.pt ([193.137.203.231] helo=smtp.dei.uc.pt) by ietf-mx.ietf.org with esmtp (Exim 4.43) id 1Ec37J-00080D-5r for ssm@ietf.org; Tue, 15 Nov 2005 10:53:08 -0500 Received: from laptop (din-cisuc245.dei.uc.pt [10.3.1.245]) (authenticated bits=0) by smtp.dei.uc.pt (8.13.4/8.13.4) with ESMTP id jAFFaIVn015123 (version=TLSv1/SSLv3 cipher=RC4-MD5 bits=128 verify=NO); Tue, 15 Nov 2005 15:36:18 GMT Message-Id: <200511151536.jAFFaIVn015123@smtp.dei.uc.pt> From: "Tiago Sousa" To: "'Toerless Eckert'" Subject: RE: [ssm] IPv6 Multicast Throughput problems in 802.11 Date: Tue, 15 Nov 2005 15:34:31 -0000 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Office Outlook, Build 11.0.6353 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2527 Thread-Index: AcXp+AtCqHwwwE+cQgaMQZVosoeSAgAAJseA In-Reply-To: <20051115151655.GL19539@cisco.com> X-FCTUC-DEI-SIC-MailScanner-Information: Please contact helpdesk@dei.uc.pt for more information X-FCTUC-DEI-SIC-MailScanner: Found to be clean X-FCTUC-DEI-SIC-MailScanner-SpamCheck: not spam (whitelisted), SpamAssassin (score=-4.399, required 3, autolearn=not spam, ALL_TRUSTED -1.80, BAYES_00 -2.60) X-FCTUC-DEI-SIC-MailScanner-From: tmas@dei.uc.pt X-Spam-Score: 0.0 (/) X-Scan-Signature: 41c17b4b16d1eedaa8395c26e9a251c4 Content-Transfer-Encoding: 7bit Cc: ssm@ietf.org X-BeenThere: ssm@ietf.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Source-Specific Multicast List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: ssm-bounces@ietf.org Errors-To: ssm-bounces@ietf.org Thanks for your reply. What packet size do you use ? I've used already several packet sizes with minimal consequences on wireless multicast throughput. At least when compared with the strong decrease that I am seeing in my results. The best results, as expect, happens with UDP packet size of 1500 bytes. There's also a configuratin on access-points for how much bandwidth multicast (aka: broadcast) can use. That's often tuned down to a very low default value. My access point is a Belkin 54g (F5D7130) and, at least, through the web page I can't see anything related with multicast or broadcast. I've used successfully multiple megabits across 802.11b, not sure what your problem is... At this point neither do i... Thanks. Tiago On Tue, Nov 15, 2005 at 02:26:04AM -0000, Tiago Sousa wrote: > Hello to all > > > > I am testing the PIM-SSM daemon (both freebsd and linux) and mrd6 (another > IPv6 multicast routing daemon) in a wireless link. > > The problem I encountered with both pim6sd daemon and mrd6 is that I'm > sending multicast traffic at 4 Mbps and the throughput in the mobile node > (which is very near from de access point) rounds 40 kbps. > > I am using the mad-flute tool to send the multicast SSM traffic and the > tcpdump plus trpr to analyze the data. I have also used IxChariot and the > results are the same. > > > > Anyone knows why the throughput decreases so much in the wireless link? > (The multicast TTL is well defined, I have experimented with several > pci/pcmcia cards and drivers and several access points configurations > (different channels and rates (801.11b and 802.11g)). The results are remain > always the same). > > > > I would appreciate any help/hint that helps me to explain these results. > > > > Thanks. > > > > Tiago Sousa _______________________________________________ ssm mailing list ssm@ietf.org https://www1.ietf.org/mailman/listinfo/ssm _______________________________________________ ssm mailing list ssm@ietf.org https://www1.ietf.org/mailman/listinfo/ssm From ssm-bounces@ietf.org Tue Nov 15 10:52:01 2005 Received: from localhost.cnri.reston.va.us ([127.0.0.1] helo=megatron.ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1Ec36H-000645-MS; Tue, 15 Nov 2005 10:52:01 -0500 Received: from odin.ietf.org ([132.151.1.176] helo=ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1Ec36G-00063x-4k for ssm@megatron.ietf.org; Tue, 15 Nov 2005 10:52:00 -0500 Received: from ietf-mx.ietf.org (ietf-mx [132.151.6.1]) by ietf.org (8.9.1a/8.9.1a) with ESMTP id KAA02091 for ; Tue, 15 Nov 2005 10:51:27 -0500 (EST) Received: from zproxy.gmail.com ([64.233.162.193]) by ietf-mx.ietf.org with esmtp (Exim 4.43) id 1Ec3NV-0000Bc-9n for ssm@ietf.org; Tue, 15 Nov 2005 11:09:50 -0500 Received: by zproxy.gmail.com with SMTP id 9so996994nzo for ; Tue, 15 Nov 2005 07:51:55 -0800 (PST) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=O6krkknU8ZBfeme+7nFvP6V1hQLBFCa7RQfPJ/jBAHRFt90oRPXTn9WdH/fMti6Yiu7tMAqHxeMrZjqjkhl+CEQh1jjWfXQhmSZ2VKI+3rN7SdQjANzFCoemNKcgPVnC+4Ez/Uu/Ikgoc0aBzljI2HuGC/fdv4UdJSByLHphTKo= Received: by 10.36.247.5 with SMTP id u5mr5210795nzh; Tue, 15 Nov 2005 07:51:55 -0800 (PST) Received: by 10.36.46.2 with HTTP; Tue, 15 Nov 2005 07:51:55 -0800 (PST) Message-ID: Date: Tue, 15 Nov 2005 10:51:55 -0500 From: Marshall Eubanks To: Tiago Sousa Subject: Re: [ssm] IPv6 Multicast Throughput problems in 802.11 In-Reply-To: <200511150227.jAF2Rkbu025768@smtp.dei.uc.pt> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline References: <200511150227.jAF2Rkbu025768@smtp.dei.uc.pt> X-Spam-Score: 0.0 (/) X-Scan-Signature: 41c17b4b16d1eedaa8395c26e9a251c4 Content-Transfer-Encoding: quoted-printable Cc: ssm@ietf.org X-BeenThere: ssm@ietf.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Source-Specific Multicast List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: ssm-bounces@ietf.org Errors-To: ssm-bounces@ietf.org Well, one cool thing about 802.11 is that you can generally see every packe= t. Have you used tcpdump to see if the packets get placed into the air ? That should distinguish between broken packets (they are there, but=20 fragmented or have some other problem) and some filtering happening in the access point = or upstream. If they aren't, you should be able to put a hub at the AP or look on the AP LAN and see if they are _reaching_ the AP. (You can join the group on the AP LAN if it is not broadcasting multicast) If they are, then it's an AP problem. If I had to guess, I would suspect an AP problem, but it's good to know for sure. Regards Marshall On 11/14/05, Tiago Sousa wrote: > > > > Hello to all > > > > I am testing the PIM-SSM daemon (both freebsd and linux) and mrd6 (anothe= r > IPv6 multicast routing daemon) in a wireless link. > > The problem I encountered with both pim6sd daemon and mrd6 is that I'm > sending multicast traffic at 4 Mbps and the throughput in the mobile node > (which is very near from de access point) rounds 40 kbps. > > I am using the mad-flute tool to send the multicast SSM traffic and the > tcpdump plus trpr to analyze the data. I have also used IxChariot and the > results are the same. > > > > Anyone knows why the throughput decreases so much in the wireless link? > (The multicast TTL is well defined, I have experimented with several > pci/pcmcia cards and drivers and several access points configurations > (different channels and rates (801.11b and 802.11g)). The results are rem= ain > always the same). > > > > I would appreciate any help/hint that helps me to explain these results. > > > > Thanks. > > > > Tiago Sousa > > > _______________________________________________ > ssm mailing list > ssm@ietf.org > https://www1.ietf.org/mailman/listinfo/ssm > > > _______________________________________________ ssm mailing list ssm@ietf.org https://www1.ietf.org/mailman/listinfo/ssm From ssm-bounces@ietf.org Tue Nov 15 11:21:30 2005 Received: from localhost.cnri.reston.va.us ([127.0.0.1] helo=megatron.ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1Ec3Yo-0006UA-Ji; Tue, 15 Nov 2005 11:21:30 -0500 Received: from odin.ietf.org ([132.151.1.176] helo=ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1Ec3Ym-0006U5-Nd for ssm@megatron.ietf.org; Tue, 15 Nov 2005 11:21:29 -0500 Received: from ietf-mx.ietf.org (ietf-mx [132.151.6.1]) by ietf.org (8.9.1a/8.9.1a) with ESMTP id LAA04903 for ; Tue, 15 Nov 2005 11:20:55 -0500 (EST) Received: from smtp2.dei.uc.pt ([193.137.203.231] helo=smtp.dei.uc.pt) by ietf-mx.ietf.org with esmtp (Exim 4.43) id 1Ec3q2-0001Gu-2R for ssm@ietf.org; Tue, 15 Nov 2005 11:39:19 -0500 Received: from laptop (din-cisuc245.dei.uc.pt [10.3.1.245]) (authenticated bits=0) by smtp.dei.uc.pt (8.13.4/8.13.4) with ESMTP id jAFGMoFE020867 (version=TLSv1/SSLv3 cipher=RC4-MD5 bits=128 verify=NO); Tue, 15 Nov 2005 16:22:50 GMT Message-Id: <200511151622.jAFGMoFE020867@smtp.dei.uc.pt> From: "Tiago Sousa" To: "'Marshall Eubanks'" Subject: RE: [ssm] IPv6 Multicast Throughput problems in 802.11 Date: Tue, 15 Nov 2005 16:21:03 -0000 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Office Outlook, Build 11.0.6353 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2527 Thread-Index: AcXp/X4C726x849QQImMN35qtWjLCgAAZyQg In-Reply-To: X-FCTUC-DEI-SIC-MailScanner-Information: Please contact helpdesk@dei.uc.pt for more information X-FCTUC-DEI-SIC-MailScanner: Found to be clean X-FCTUC-DEI-SIC-MailScanner-SpamCheck: not spam (whitelisted), SpamAssassin (score=-4.399, required 3, autolearn=not spam, ALL_TRUSTED -1.80, BAYES_00 -2.60) X-FCTUC-DEI-SIC-MailScanner-From: tmas@dei.uc.pt X-Spam-Score: 0.0 (/) X-Scan-Signature: 10d3e4e3c32e363f129e380e644649be Content-Transfer-Encoding: 7bit Cc: ssm@ietf.org X-BeenThere: ssm@ietf.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Source-Specific Multicast List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: ssm-bounces@ietf.org Errors-To: ssm-bounces@ietf.org Thanks for the reply. Well, one cool thing about 802.11 is that you can generally see every packet. Have you used tcpdump to see if the packets get placed into the air ? Yes. I sniff the router outgoing interface where the AP is connect and I can see the packets flying to air. That should distinguish between broken packets (they are there, but fragmented or have some other problem) and some filtering happening in the access point or upstream. It is true. The majority of times I see fragmented packets in the outgoing interface. Do you think that AP is filtering this fragmented packets? Why? If they aren't, you should be able to put a hub at the AP or look on the AP LAN and see if they are _reaching_ the AP. (You can join the group on the AP LAN if it is not broadcasting multicast) If they are, then it's an AP problem. If I had to guess, I would suspect an AP problem, but it's good to know for sure. I will find another AP and try. Thanks. Tiago Sousa Regards Marshall On 11/14/05, Tiago Sousa wrote: > > > > Hello to all > > > > I am testing the PIM-SSM daemon (both freebsd and linux) and mrd6 (another > IPv6 multicast routing daemon) in a wireless link. > > The problem I encountered with both pim6sd daemon and mrd6 is that I'm > sending multicast traffic at 4 Mbps and the throughput in the mobile node > (which is very near from de access point) rounds 40 kbps. > > I am using the mad-flute tool to send the multicast SSM traffic and the > tcpdump plus trpr to analyze the data. I have also used IxChariot and the > results are the same. > > > > Anyone knows why the throughput decreases so much in the wireless link? > (The multicast TTL is well defined, I have experimented with several > pci/pcmcia cards and drivers and several access points configurations > (different channels and rates (801.11b and 802.11g)). The results are remain > always the same). > > > > I would appreciate any help/hint that helps me to explain these results. > > > > Thanks. > > > > Tiago Sousa > > > _______________________________________________ > ssm mailing list > ssm@ietf.org > https://www1.ietf.org/mailman/listinfo/ssm > > > _______________________________________________ ssm mailing list ssm@ietf.org https://www1.ietf.org/mailman/listinfo/ssm _______________________________________________ ssm mailing list ssm@ietf.org https://www1.ietf.org/mailman/listinfo/ssm From ssm-bounces@ietf.org Tue Nov 15 11:45:38 2005 Received: from localhost.cnri.reston.va.us ([127.0.0.1] helo=megatron.ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1Ec3wA-0007ha-LH; Tue, 15 Nov 2005 11:45:38 -0500 Received: from odin.ietf.org ([132.151.1.176] helo=ietf.org) by megatron.ietf.org with esmtp (Exim 4.32) id 1Ec3w9-0007gt-6b for ssm@megatron.ietf.org; Tue, 15 Nov 2005 11:45:37 -0500 Received: from ietf-mx.ietf.org (ietf-mx [132.151.6.1]) by ietf.org (8.9.1a/8.9.1a) with ESMTP id LAA06847 for ; Tue, 15 Nov 2005 11:45:03 -0500 (EST) Received: from zproxy.gmail.com ([64.233.162.205]) by ietf-mx.ietf.org with esmtp (Exim 4.43) id 1Ec4DM-0002DS-7u for ssm@ietf.org; Tue, 15 Nov 2005 12:03:24 -0500 Received: by zproxy.gmail.com with SMTP id 9so1009802nzo for ; Tue, 15 Nov 2005 08:45:32 -0800 (PST) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=Hap+ncdV0xb9pnaxa7vkE8XDHp9s6jE5hFcRORgsRRLxSztQMvUfWUUyI6zIohshkZ35mZV80Fuuzpsl/dfMXTjMlK0GKg3k+xx1LApfuwDQsQpKLQZMNZi/rJBUTyhM8Rpc4lvR7Cbzy1JUXYxyPilFfpB1IMlg6+07Q/OfESo= Received: by 10.37.18.77 with SMTP id v77mr5291514nzi; Tue, 15 Nov 2005 08:45:32 -0800 (PST) Received: by 10.36.46.2 with HTTP; Tue, 15 Nov 2005 08:45:32 -0800 (PST) Message-ID: Date: Tue, 15 Nov 2005 11:45:32 -0500 From: Marshall Eubanks To: Tiago Sousa Subject: Re: [ssm] IPv6 Multicast Throughput problems in 802.11 In-Reply-To: <200511151622.jAFGMoFE020867@smtp.dei.uc.pt> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline References: <200511151622.jAFGMoFE020867@smtp.dei.uc.pt> X-Spam-Score: 0.0 (/) X-Scan-Signature: 2ed806e2f53ff1a061ad4f97e00345ac Content-Transfer-Encoding: quoted-printable Cc: ssm@ietf.org X-BeenThere: ssm@ietf.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Source-Specific Multicast List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: ssm-bounces@ietf.org Errors-To: ssm-bounces@ietf.org Hello; On 11/15/05, Tiago Sousa wrote: > Thanks for the reply. > > Well, one cool thing about 802.11 is that you can generally see every > packet. > > Have you used tcpdump to see if the packets get placed into the air ? > > Yes. I sniff the router outgoing interface where the AP is connect and I = can > see the packets flying to air. > > That should distinguish between broken packets (they are there, but > fragmented or > have some other problem) and some filtering happening in the access poin= t > or > upstream. > > It is true. The majority of times I see fragmented packets in the outgoin= g > interface. Do you think that AP is filtering this fragmented packets? Why= ? > That sounds bad. A lot of stuff will drop fragmented packets, or maybe the router CPU will be overloaded by them, so IMHO they should be avoided if at all possible. Now the question is, where are they fragmented and why ? Your AP might not forward fragmented packets at all, for example. It sounds like it if I am reading your comments correctly. Possible reasons are - an IPv6 tunnel (over IPv4 ?) - lots of times, people forget about the tun= nel overhead in doing static MTU calculations. Maybe it's going through a tunne= l within a tunnel. Maybe it's the extra size of the IPv6 headers. - Something broken in configurations or ... . If you look at packet sizes going into the router and going out of the router (or where-ever the fragmentation is occuring),= you should be able to figure out the _actual_ MTU. That may or may not match the _configured_ MTU. - Something broken, period. If all else fails, try a different NIC card. If you can sniff upstream, you should be able to at least find out where the packets are fragmented. > If they aren't, you should be able to put a hub at the AP or look on > the AP LAN and see if they are _reaching_ the AP. (You can join the > group on the AP LAN if it is not broadcasting multicast) If they are, > then it's an AP problem. If I had to guess, > I would suspect an AP problem, but it's good to know for sure. > > I will find another AP and try. > That sounds like a good idea, but you still need to make sure that - packets are getting to the router unfragmented - 98% of the packets are fragmented by the time they reach the AP (to get f= rom 2 Mbps to 40 Kbps). - the AP is dropping these. - what box is actually doing the fragmentation. (For example, is there a switch in the path ? A firewall ?) I suspect you're pretty close to figuring this one out. Regards Marshall > Thanks. > > Tiago Sousa > > Regards > Marshall > > On 11/14/05, Tiago Sousa wrote: > > > > > > > > Hello to all > > > > > > > > I am testing the PIM-SSM daemon (both freebsd and linux) and mrd6 (anot= her > > IPv6 multicast routing daemon) in a wireless link. > > > > The problem I encountered with both pim6sd daemon and mrd6 is that I'm > > sending multicast traffic at 4 Mbps and the throughput in the mobile no= de > > (which is very near from de access point) rounds 40 kbps. > > > > I am using the mad-flute tool to send the multicast SSM traffic and the > > tcpdump plus trpr to analyze the data. I have also used IxChariot and t= he > > results are the same. > > > > > > > > Anyone knows why the throughput decreases so much in the wireless link? > > (The multicast TTL is well defined, I have experimented with several > > pci/pcmcia cards and drivers and several access points configurations > > (different channels and rates (801.11b and 802.11g)). The results are > remain > > always the same). > > > > > > > > I would appreciate any help/hint that helps me to explain these results= . > > > > > > > > Thanks. > > > > > > > > Tiago Sousa > > > > > > _______________________________________________ > > ssm mailing list > > ssm@ietf.org > > https://www1.ietf.org/mailman/listinfo/ssm > > > > > > > > _______________________________________________ > ssm mailing list > ssm@ietf.org > https://www1.ietf.org/mailman/listinfo/ssm > > _______________________________________________ ssm mailing list ssm@ietf.org https://www1.ietf.org/mailman/listinfo/ssm